System of electrical distribution.



No. 867,065. PATENTBD SEPT. 24, 1907.

L. o. MARBURG. SYSTEM OF ELECTRICAL msmnumou APPLIOATIOI FILED AUG. 30.1006.

Inventor: Louis C-JZarluy- 24 y fl Attorney- UNITED STATES PATENTOFFICE.

LOUIS O. MARB'UR-Cr, OF NORWOOD, OHIO, ASSIGNOR TO THE BULLOCK ELECTRICI'I'ANUFrWTURING COMPANY, A OORPORATITION OF OHIO.

SYSTEM OF ELECTRICAL DISTRIBUTION.

Specification of Letters Patent.

Patented Sept. 24, 1907.

Application filed August 30,1905. Serial No. 276,332.

To all whom it. may concern:

Be it known that I, LOUIS O. MARBURG, a citizen of the United States,residing at Norwood, in the county of Hamilton and State of Ohio, haveinvented certain new and useful Improvements in Systems of ElectricalDistribution, of which the following is a full, clear, and exactspecification.

This invention relates to a system of electrical distribution in whichenergy in the form of alternating current is transformed into directcurrent by means of a single or a plurality of converters.

It has been found that when two or more converters are conductivelyconnected together on both the alternating and direct current sides, aswhen converters in a main power station or in a' sub-station nearby areconnected directly to the low-tension bus-bars in the power station, theconverters do not operate satisfactorily, probably on account of thecross currents flowing through the short circuit including theconverters and the connecting leads on the alternating and directcurrent sides.

One of the objects of my invention is to provide a means for operatingtwo or more converters in the power station, or a nearby sub-station,directly from the low-tension bus-bars in the power station, withoutnecessitating the use of both step-up and step-down transformers, whichinvolve considerable expense, and without otherwise conductivelyconnecting the converters on the alternating current side.

A further object is to provide a convenient means for connecting one ormore converters to an alternating current system.

In. carrying out my invention, I provide a transformer having ahigh-tension winding, and a plurality of independent low-tensionwindings adapted to be connected to the bus-bars or the converters. Theconverters may be supplied with current directly by the generators orone or more may be connected to lowtension windings and supplied withcurrent by induction from one or more low-tension windings which areconnected to the bus-bars and to one or more generators.

Considering my invention from a more specific standpoint, I providebus-bars scctionalized by means of switches, or a plurality ofindependent sets of bus-bars, a plurality of generators, a plurality ofrotary converters, and a transformer having a high-tension winding and aplurality of low-tension windings, each generator, converter, andlow-tension winding being provided with switches whereby I may connecteach set or section of bus-bars to one or more generators, to aconverter, and to a low-tension winding, or I may connect one, two, orall the generators to a set or section of bus-bars to which alow-tension winding is connected, and connect another low-tensionwinding to a converter.

i the generator and converter.

My invention further consists in certain novel arrangements andcombinations of parts described in the specification and set forth inthe appended claims.

Referring to the drawing, which represents diagrammatically a system ofdistribution involving my invention, I have shown at 1, 1 twoindependent sets or sections of low-tension bus-bars, adapted to beconnected, if desired, by the switch 2, the bus-bars being fed in thiscase by the three-phase generators 3 and 3. Switches f and 4 areinserted between the generators and the corresponding bus-bars forconnecting or dis connecting, one or more generators at will. At 5 and 5are shown two rotary converters which are intended to be located in apower station or a nearby sub-station and to be connected to thealternating current generators and to the direct current mains. Betweeneach converter and the corresponding bus-bars are suitable switches 6and 6 for connecting or disconnecting at will any one of the converters.I have shown at 7 a three-phase step-up transformer, the high tensionside 8 of which is adapted to be connected to a transmission or feedercircuit. The low-tension side of this transformer consists of two ormore entirely independent windings 9 and 9 adapted to be connectedrespectively by switches 11 and 11 to the sections or sets of thebusbars. As I have in this case shown only two sets of bus-bars, I haveshown only two independent lowtension windings, but it is to beunderstood that it more than two sets of bus-bars are used, there wouldpreferably be a corresponding number of independent low tensionwindings, each adapted to be connected to one set of busbars.

The manner of connecting the various parts of the apparatus underdifferent conditions of load and the results obtained will now beexplained. If it is desired to operate both generators and bothconverters, the switches i, 4 and (3, ti will be closed and thesectionalizing switch 2 will be opened. It will be seen that eachgenerator will supply one converter and at the same time supply one-halfof the low-tension side of the transformer 7. If for any reason it isdesired to operate one generator and two converters, one generatorswitch, both converter switches and both transformer switches will beclosed, but the bus-sectionalizing switch 2 will be opened. In this caseone converter will be supplied through the two low-tension windings ofthe transformer, the two windings acting in this case as a one-to-oneratio transformer. If it is desired to operate converter ofrom generator3, converter 5 being shut down, the bus-sectionalizing switch 2 will beclosed and converter 5 will be supplied direct from the generator 3. Ina similar manner converter 5 can be fed direct from generator 3. It isto be noted in the two latter cases that there is no transformer betweenIf it is desired to operate either converter from both generators, thebussectionalizing switch will be closed.

It will be seen that the generators and converters can be connected in avariety of ways for various purposes and conditions of load, and in nocase will the converters be conductively connected together on both thealternating current and direct current sides, therefore there will be noclosed electric circuit for the objectional cross-currents. I have shownin this case two generators and two converters, and I have explained howeach converter can be operated directly from a separate generator, orboth from a single generator, one being connected direct to thegenerator and the other to the generator through the low-tensiontransformer windings. 'I wish it understood however, that the number ofgenerators and converters employed may be widely varied. I have shown inthis case rotary converters, but it is apparent that my invention can beemployed with equal effect with converters of any other type which havealternating and direct current terminals conductively connectedtogether.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is 1. In a system of distribution, a pluralityof low-tension bus-bars, a source of alternating current comprisinggenerators adapted to be connected to said bus-bars, a transformerhaving separate windings connected to said bus-bars, a plurality ofconverters, and means for connecting the converters to the source ofcurrent in such a manner that the converters are not conductivelyconnected together on the alternating current side.

2. In a system of distribution, a'plurality of low ten sion bus-bars oralternating current connections, -a plu rality of generators adapted tobe connected to or disconnected therefrom at will, a transformer havinga plurality of separate low-tension windings connected to said bus-l arsor connections, a plurality of converters, and means for connecting saidconverters to said bus-bars or connections in such a manner that theconverters are not conductively connected together on the alternatingcurrent side.

In a system of distribution, an alternating current generator, atransformer having a high-tension winding anda plurality of low-tensionwindings, means for con meeting the generator to one of said low-tensionwindings, a converter, and means for connecting the converter to anotherof said low-tension windings.

4. In a system of distribution, one or more alternating currentgenerators, a transformer having a plurality of low-tension windings,means for connecting the generator or generators to one of saidlow-tension windings, one or more converters, and means for connecting aconverter to another low-tension winding.

5. In a system of distribution, a source of alternating current, atransformer having a high-tension winding and apluraliity of independentlow-tension windings, a plurality of converters, and means forconnecting the source of current to one of said low-tension windings andto a converter, and a second converter to a second low tension winding.

6. In a system of distribution, a source of alternating current, astep-up transformer having a high-tension winding and a pair oflow-tension windings, a pair of converters, means for connecting thesource of current to one of said lowtension windings and to one of saidconverters and means for connecting the second of said converterstoanother of the low-tension windings.

T. [n a system of distribution, a plurality of independent alternatingcurrent generators, a transformer having a high-tension winding and aplurality of low tension windings, means for connecting each of saidgenerators to one of said low-tension windings, a plurality ofconverters, and means for connecting each of said converters to one ofsaid generators.

8. In a system of distribution, a plurality of alternating currentgenerators, each adapted to be connected independently to a section orset of sectionalized bus-bars, a transformer having a high-tensionwinding and a plurality of independent low-tension windings, a pluralityof converters, means for connecting one set of bus-bars to one or moregenerators, to one low-tension winding and to one converter, and meansfor connecting another set of bushars to another low-tension winding andto another con verter.

9, In a system of distribution, a plurality of alternating currentgenerators, a transformer having a high-tension winding, and a pluralityof low-tension windings, a plurality of converters and means forconnecting one or more generators to each of said low-tension windingsand to one of said converters. 1 I

10. In a system of distribution, a plurality of alternating currentgenrators, a transformer having a plurality of low-tension windings, aplurality of converters, means for connecting a generator to eachlow-tension winding and to a converter, or for disconnecting thegenerator from a low-tension winding and for connecting a con verteronly to said winding, so that the converters are not conductivelyconnected together on the alternating cur rent side.

In testimony whereof I atfix my signature, in the presence of twowitnesses.

LOUIS C. MARBURG.

Witnesses AIt'lI-IUR F. KwIs, FRED J. KINSEY.

